In the food packaging industry, there is a growing trend in the market for portion-control packaging. This is beneficial for convenience, lunches for children and adults, and caloric control.
Multi-cellular containers sold as a one-piece unit have been used in the yogurt industry. The cups are made from polystyrene and the consumer may remove one of the cells by bending along a cut-score of the package and breaking it off. This allows the consumer to open one cup at a time without disturbing the remaining cups, however, polystyrene is not suited for some food packaging applications. Polystyrene forms a poor moisture barrier. Polystyrene forms a brittle container, subject to cracking and breaking.
To date, no multi-cellular packages have been produced in polypropylene similar to the polystyrene yogurt cups. Attempts have been made to perforate polypropylene for use in multi-cellular containers, but this process leaves rough and sharp edges along the break region between the containers. These rough and sharp edges may cut or injure the user.